The present invention relates to a cooling system and more particularly to a supermarket cooling system in which a plurality of diverse cooling loads are served by respective compressors pumping into a common high side header.
As is understood by those skilled in the art, a modern large scale supermarket typically involves a multitude of diverse cooling demands. Frequently, these diverse demands are met by many separate independent systems, each limited by its own peculiar constraints so that each system is not particularly efficient and there is no overall thermal management so as to minimize the consumption of energy, typically provided in the form of electrical power.
At one end of the spectrum of diverse loads present in the supermarket environment are typically the ice cream cases which must produce an evaporator temperature in the order of -30 degrees F. corresponding to a suction manifold pressure about 9 pounds per square inch. At the other end of the spectrum is typically the air conditioning system where the evaporator temperature will be about 40 degrees F., corresponding to a suction pressure of about 80 pounds per square inch. In between these range extremes are the frozen foods coolers, the meat coolers and the vegetable chillers which require corresponding intermediate evaporator temperatures and suction pressures. These suction pressures are typical for common refrigerant such as R502 and assume a design high side pressure of about 200 psi.
In conventional supermarket architectures, separate refrigerant loops are provided for each type of load, if not for each individual load. Thus, not only are multiple compressors required, but multiple condensers are likewise required, together with any auxiliary valving heat exchange equipment, etc. which may be employed.
As is understood, the thermal efficiency of at least some of the loads can be cost-effectively improved by providing sub-cooling of the refrigerant after condensing. Likewise, for larger systems, some of the heat ejected from the refrigerant may be reclaimed, e.g., for use in reheating the air in the store during the cooler seasons or to provide reheat for dehumidification.
Among the several objects of the present invention may be noted the provision of a cooling system of increased overall efficiency; the provision of such a cooling system which is adapted to serve multiple diverse cooling loads; the provision of such a system of which eliminates the need for respective condensers for multiple diverse cooling loads; the provision of such a system which provides for essentially free sub-cooling of refrigerant without substantially adding to equipment costs; the provision of such a cooling system which provides for heat reclamation in a more efficient and cost effective manner; the provision of such a systemin which air conditioning and refrigeration loads are efficiently integrated; the provision of such a system which is highly reliable; the provision of such a system which is highly efficient overall and is of relatively simple and inexpensive construction.
Other objects and features will be in part apparent and in part pointed out hereinafter.